In stores, factories, banks and other business establishments where theft and other dangerous or undesirable activities are sought to be guarded against, it has become common practice to install monitoring cameras in strategic locations within such facilities to either continuously or intermittently record ongoing activities therein.
Such monitoring cameras can be self-contained power operated time-lapse photographic cameras or television monitoring cameras connected with remote video tape recorders or the like. Whichever of these two basic types of cameras are employed, they are, for economic and other equally important reasons, made as simple and as economical as is practical. As a result of the foregoing, many monitoring cameras are simple, substantially rectangular box-like units having lenses projecting from one end thereof, and do not include costly and space consuming accessories such as view finders.
As a result of the above, when installing and setting surveillance cameras which do not include view finders, great care and skill must be exercised by the installers of such cameras to assure that those areas to be monitored are within the fields of veiw of the cameras.
At the present time, the most common procedure is to estimate the area of coverage by each camera and then through trial and error and the developing of photographs, change the angular position and relationship of the cameras until the desired result is achieved.